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| MOAP01 | Approach to a very high intensity beam at J-PARC | linac, injection, hadron, rfq | 1 | ||
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| MOAP02 | Recent Beam Commissioning Results from the Spallation Neutron Source | linac, target, extraction, emittance | 6 | ||
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The Spallation Neutron Source accelerator complex consists of a 2.5 MeV H- front-end injector system, a 186 MeV normal-conducting linear accelerator, a 1 GeV superconducting linear accelerator, an accumulator ring and associated beam transport lines. The beam commissioning campaign of the SNS accelerator complex, initiated in 2002, has been performed in seven discrete runs as each successive portion of the accelerator complex has been installed. The final beam commissioning run, in which beam was transported to the liquid mercury target was recently completed. In the course of beam commissioning, most beam performance parameters and beam intensity goals have been achieved at low duty factor. The beam performance and beam dynamics measurements of the linac and ring will be presented.
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| MOAP03 | Comparative Studies of Proton Accelerators for High Power Applications | target, factory, linac, klystron | 11 | ||
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There are many applications need high power proton accelerators of various kinds. However, each type of proton accelerator can only provide beam with certain characteristics, hence the match of accelerators and their application needs careful evaluation. In this talk, the beam parameters and performance limitations of linac, cyclotron, synchrotron, and FFAG accelerators will be studied and their relative merits for application in muon, neutron, neutrino, and ADS assessed in terms of beam energy, intensity, bunch length, repetition rate, and beam power requirements. A possible match between the applications and the accelerator of choice will be presented in a matrix form. The accelerator physics and technology issues and challenges involved will also be covered.
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| MOAP04 | Recent progresses on FFAG accelerators | acceleration, focusing, target, emittance | 16 | ||
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| MOBP01 | ISIS Upgrades – A Status Report | synchrotron, target, linac, rfq | 20 | ||
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Since 2002 several accelerator upgrades have been made to the ISIS spallation neutron source at the Rutherford Appleton Laboratory in the UK, and upgrades are currently continuing in the form of the Second Target Station Project. The paper will review the upgrade processes, and will also look forward to possible future schemes at ISIS beyond the Second Target Station.
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| MOBP03 | Upgrade of BNL Accelerator Facility | luminosity, ion, electron, heavy-ion | 29 | ||
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A number of upgrades are planned for the Brookhaven accelerator facility that is primarily made of RHIC and its injector, the AGS. The RHIC luminosity and proton polarization are to evolve towards the Enhanced Design parameters by 2008. A new Electron Beam Ion Source is under development, and commissioning is expected in 2009. The aim of the RHIC II upgrade is to increase the heavy ion luminosity by an order of magnitude, through electron cooling in store. With the addition of an electron ring, the high-luminosity electron-ion collider proposal eRHIC can be realized. Studies have also been done for a new injector to the AGS replacing the present Booster for an upgrade of the beam average power to 1 MW at 28 GeV. The new injector to match the AGS repetition rate can be either a 1.5-GeV SCL or a FFAG accelerator. With the upgrade of the injector complex, neutrino superbeams could be produced.
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| MOCP01 | Beam intensity upgrade at Fermilab | booster, target, antiproton, extraction | 34 | ||
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| MOCP02 | High-power accelerators in China: status and outlook | linac, target, injection, dipole | 39 | ||
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High intensity accelerator research is a relatively new subject in China. Recent program includes the accelerator-driven sub-critical power generation and the Beijing Spallation Neutron Source (BSNS) project. The Beijing Spallation Neutron Source (BSNS) is a newly approved project based on a H- linear accelerator and a rapid cycling synchrotron. During the past year, several major revisions were made on the design including the type of the front end, the linac frequency, the transport layout, the ring lattice, and the type of ring components. Possible upgrade paths were also laid out: based on an extension of the warm linac, the ring injection energy and the beam current could be raised doubling the beam power on target to reach 200 kW; an extension with a superconducting RF linac of similar length could raise the beam power near 0.5 MW. Based on these considerations, research and development activities are started. In this paper, we discuss the rationale of design revisions and summarize the recent works.
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| MOCP03 | Status of the LHC | luminosity, injection, cryogenics, superconducting-magnet | 44 | ||
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For the LHC to provide particle physics with proton-proton collisions at a centre of mass energy of 14 TeV with a luminosity of 1034 cm-2s-1, the machine will operate with high-field dipole magnets using NbTi superconductors cooled to below the λ point of helium. The construction follows a decade of intensive R&D and technical validation of major collider sub-systems. Installation of the accelerator system is in full swing. Commissioning of the injector complex is well advanced, including beam transfer through one of the transfer lines from SPS to LHC. In the LHC machine, commissioning of the cryogenic system and powering system has started. The status of the LHC accelerator and a brief outlook to operation and its consequences for the machine protection systems will be given. The strategy for the machine protection and beam cleaning will have a major impact on commissioning and operation since each of the two LHC proton beam has a stored energy of about 360 MJ. A fraction of less than 10-3 of the full beam threatens to damage accelerator equipment in case of uncontrolled beam loss, and only 10-8 protons could already quench a magnet.
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| TUAY01 | Overview of proton driver studies for neutrino and muon factories | linac, synchrotron, factory, target | 64 | ||
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There are a number of proton driver studies around the world: SPL at CERN, an 8 GeV SCRF linac at Fermilab, AGS upgrade at BNL, Proton Driver for the International Scoping Study on Neutrino Factories and Superbeams, FFAG based proton driver in Japan, etc. This talk will give an overview of them and compare their similarities and differences. Common R&D projects and possible inter-laboratory collaborations will be discussed.
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| TUAY04 | Beam Dynamics Design of the PEFP 100 MeV Linac | linac, quadrupole, emittance, rfq | 99 | ||
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The Proton Engineering Frontier Project (PEFP) is constructing a 100 MeV proton linac in order to provide 20 MeV and 100 MeV proton beams. The linac consists of a 50 keV proton injector including an ion source and a low energy beam transport (LEBT), a 3 MeV radio-frequency quadrupole (RFQ), a 20 MeV drift tube linac (DTL), a medium energy beam transport (MEBT), and the higher energy part (20 MeV ~ 100 MeV) of the 100 MeV DTL. The MEBT is located after the 20 MeV DTL to extract 20 MeV proton beams. The 20 MeV part of the linac was completed and is now under beam test. The higher energy part of the PEFP linac was designed to operate with 8% beam duty. This brief report discusses the design of the PEFP 100MeV linac as well as the MEBT.
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| TUAZ02 | High-Intensity Beam Collimation and Targetry | collimation, target, beam-losses, radiation | 74 | ||
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Principles, design criteria and realization are described for reliable collimation systems for the high-power accelerators (Fermilab Booster and Main Injector, SNS, J-PARC), hadron colliders (Tevatron and LHC) and e+e- linear colliders (ILC). Factors affecting the expected and achieved collimation performances are analyzed. Functionality of collimators as the key elements of the machine protection system are considered using as an example a recent beam accident case in the Tevatron. A substantial progress on the crystal collimation front is described. The key issues are considered in design of high-power target systems and achieving their best performance. Simulation code requirements and recent benchmarking results are presented. A status of conventional neutrino targets and neutrino factory target concepts is described along with performed and planned beam tests. Overview of the target and collimator material beam tests concludes this report.
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| TUAZ05 | Comparison of Graphite and Diamond Structured Carbon Stripper Foils under Operational Conditions at the Los Alamos PSR | injection, radiation, beam-losses, electron | 112 | ||
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In the Los Alamos Proton Storage Ring H–Ions merge with circulating protons in a bending magnet and are stripped of their two electrons in a carbon stripper foil. The circulating protons continue to interact with the foil. Despite efforts to minimize the number of these foil hits, like “painting” of the vertical phase space, they can not totally be eliminated. As a result foil heating and radiation damage limit the lifetime of these foils. In recent years LANL has collaborated with KEK to improve the graphite foils in use at PSR and these foils now last typically for two months. Recently an alternative in the form of diamond structured carbon foils has been proposed for use at SNS. Depending on the grain size these are referred to as microcrystalline or nanocrystalline foils. Both types have been tested in PSR, with quite different results. While the microcrystalline foil failed catastrophically before production beam currents were reached the nanocrystalline foil was successfully used in normal operation for several weeks. Advantages of the diamond foil concept as well as some noteworthy differences that we observed with respect to the LANL graphite foils will be discussed here.
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| TUBY02 | Physics Design of a Multi-GeV Superconducting H-minus Linac | linac, focusing, rfq, lattice | 134 | ||
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We discuss design of a pulsed linac based on 430 independently phased superconducting resonators for acceleration of 40 mA peak current H-minus beam up to 8-GeV. Most of the voltage gain (from ~410 MeV to 8 GeV) is provided by ILC cavities and squeezed ILC-style cavities operating at 1300 MHz. Significant cost savings are expected from the use of an rf power fan out from high-power klystrons to multiple cavities. The front end of the linac operating at 325 MHz will be based on multiple-spoke cavities. A room temperature section comprised of a conventional RFQ and 16 short normal conducting H-type resonators is proposed for the initial acceleration of an H-minus or proton beam up to 10 MeV. We have developed an accelerator lattice which satisfies the beam physics and engineering specifications.
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| TUBY03 | Error study of LINAC 4 | linac, simulation, emittance, quadrupole | 137 | ||
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LINAC 4 is a normal conducting H- linac which aims to intensify the proton flux available for the CERN accelerator complex. This injector is designed to accelerate a 65 mA beam up to 180 MeV. The linac consists of 4 different types of accelerating structures: the 352 MHz IPHI-RFQ, a 352 MHz 3-tank Drift Tube Linac, a 352 MHz Coupled Cavity Drift Tube Linac, and a 704.4 MHz Side Coupled Linac to boost the beam up to the final energy. As LINAC 4 is also designed as a pre-injector for a high power superconducting linac (3.5 GeV, 4 MW) the requirements on acceptable beam emittance growth, halo formation and particle loss are extremely tight. In order to determine the tolerances on the linac components, we examined the sensitivity of the structure to errors on the accelerating field and on the focusing quadrupoles. Simulations were performed between 3 and 180 MeV with the transport code TRACEWIN to evaluate the emittance growth, energy and phase jitter, halo formation of the transported beam and the amount of lost particles. We will present results on individual sensitivities to a single error, as well as the global impact of simultaneous errors on the beam quality. We will mention a f
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| TUBY04 | Operational flexibility of the SPL as proton driver for neutrino and other applications | linac, target, factory, dipole | 150 | ||
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The pulse structure of proton linacs is determined by the linac energy, the RF system, and the maximum duty cycle of the source. Short bursts of protons in the microsecond range can be achieved by adding an accumulator ring and a reduction of the bunch length to the order of nanoseconds can be accomplished with an additional bunch compressor ring. The size of the rings along with their RF frequency determines the time structure of the proton driver output burst to hit the target. This pulse structure can be further modified using multiple fillings of the accumulator and compressor rings within one linac pulse. This paper illustrates the possible modes of operation of the SPL at CERN along with its limitations at various energies in combination with accumulator and compressor rings.
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| TUBZ01 | The Beam Diagnostics System for J-PARC Synchrotrons | injection, electron, beam-losses, pick-up | 128 | ||
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The beam diagnostics system for J-PARC synchrotrons (RCS and MR) will be presented. The design of the system will be described for high current machines. Some test results will be reported.
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| TUBZ04 | Experimental Studies of Targets and Collimators for High Intensity Beams | target, radiation, controls, isotope-production | 143 | ||
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Intense muon or neutrino beams require high-performance targets intercepting multi MW proton beams. To achieve it one must push the envelope of the current knowledge regarding material behavior and endurance for both short and long exposure. It is also true for collimator structures intercepting the halo of the intense beam under normal or the entire beam during off-normal conditions. The limitations of most materials in playing such pivotal roles have led to an extensive search and experimentation with new alloys and composites that, at first glance, appear to possess the right combination of properties satisfying target and /or collimation requirements. In this study, a number of new and “smart” materials are experimentally evaluated for resilience to radiation damage and potential use in target and collimation schemes. These include targets for the muon collider and the neutrino superbeam as well as LHC collimation. Results of the on-going experimental effort under way at BNL and involving heavy irradiation of candidate materials using 200 MeV proton beams and post-irradiation analysis for irradiation damage assessment will be presented.
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| WEAX03 | Space charge neutralization and its dynamic effects | space-charge, electron, linac, simulation | 187 | ||
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High-power accelerators are being studied for several projects including accelerator driven neutron or neutrino sources. The low energy part of these facilities has to be carefully optimized to match the beam requirements of the higher energy parts. In this low energy part, the space charge self force, induced by a high intensity beam, has to be carefully controlled. This nonlinear force can generate a large and irreversible emittance growth of the beam. To reduce the space charge (SC), neutralization of the beam charge can be done by capturing some particles of the ionised residual gas in the vacuum chamber. This space charge compensation (SCC) regime complicates the beam dynamics study. This contribution aims to modelize the beam behavior in such a regime and to give order of magnitude to the linac designer for the neutralization rise time and the induced emittance growth.
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| WEAX04 | High Intensity Cyclotron Simulations: Towards Quantitative Predictions | simulation, cyclotron, injection, space-charge | 202 | ||
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PSI operates the most powerful cyclotron worldwide to the benefit of a multi-user, cross-disciplinary research facility. The accelerator complex consists of a Cockcroft-Walton pre-injector, a 72-MeV separated sector injector cyclotron and a 590-MeV separated sector Ring Cyclotron. A beam current of 1.9 mA is routinely extracted from the Ring Cyclotron overall absolute losses are below 1·10-3. The facility has a considerable potential for further improvements, an ongoing upgrade project aims at a beam current of 3 mA. The purpose of our multi-scale three-dimensional parallel code and methods development is to make the step from qualitative to quantitative predictions. Their simulation requires the accurate three-dimensional modeling of large and complicated accelerator structures including space charge, beam lines, collimation, and in the future secondary effects. We will show methods, both numerically and computational, that we use presently and give an overview on future directions. Measurements from the cyclotrons and beamlines will be compared with simulations carried out in the frame of the high intensity upgrade program.
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| WEAY05 | New experimental results on electron cooling at COSY-Juelich | electron, injection, ion, scattering | 223 | ||
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Recent electron cooling results of a proton beam at COSY – Juelich are summarized. The influence of residual gas ions trapped in the electron beam on the cooled beam stability as well as methods to suppress the instabilities are described. Results on the numerical simulation for the formation of a crystalline proton beam in COSY using the BETACOOL code and results of experimental investigations of the cooling process at extremely low proton beam intensity are reported. Future plans are briefly addressed.
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| WEAY06 | Experimental Strategy for Realization of 3-D Beam Ordering with Use of Tapered Cooling at S-LSR | laser, ion, coupling, vacuum | 231 | ||
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At ICR, Kyoto University, an ion storage/cooler ring, S-LSR has been operated since the October, 2005. S-LSR has capability of dispersion free mode* throughout the whole circumference in order to avoid the shear heating** due to momentum dispersion of ion beam orbits. With such a mode, we need a special devise to develop necessary coupling between the longitudinal and transverse degrees of freedom for 3-dimensional laser cooling.*** A Wien Filter, in which the magnetic and electric fields overlap with strengths compensating each other for ions with a certain velocity, is to be utilized in the straight section where the usual laser cooling is applied. Due to the potential difference caused by the electric field in the Wien Filter, the difference in horizontal position of the circulating ion creates the difference of the equillibrium energy after laser cooling, which realizes "Tapered Cooling"****. In the present paper, a possible strategy of experimental approach at S-LSR toward 3-dimensional crystalline ion beams with use of the Wien Filter is to be presented.
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* M. Ikegami et al., PR-STAB,7, 120101(2004). |
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| WEAZ04 | Beam-Induced Damage to the Tevatron Components and What Has Been Done About It | controls, vacuum, kicker, dipole | 205 | ||
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The Tevatron collimators and magnets were damaged and two thirds of the superconducting ring were quenched on December 5, 2003, induced by a failure in the CDF Roman Pot detector positioning at the end of a 2-TeV proton-antiproton colliding beam store. Analysis of a failure in the abort kicker AC distribution, and detailed modeling of a misbehaved beam dynamics, induced energy deposition and ablation process in the collimator material, have provided a good understanding of the event. The improvements to the detectors, Tevatron quench protection and beam loss monitor systems to avoid such an accident in the future are described.
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| WEAZ07 | Shock wave propagation near 7 TeV proton beam in LHC collimator materials | target, coupling, radiation, electron | 241 | ||
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A study is presented to estimate the influence of the impact of a 7 TeV proton beam on the physical-mechanical material properties, such as C for collimators, and Cu elsewhere. The high energy stored in each bunch can produce a shock wave near the impacting proton beam in these materials. The theoretical model for the investigations of shock wave propagation in the collimator materials takes into account ionization, electronic excitation, and energy transfer from excited electronic subsystem in the materials to the ionic subsystem. The change of other physical properties of the material is also considered. The deposited energy is calculated with FLUKA [1]. The numerical results of the microstructure change in the material are presented for different numbers of bunches. The method allows investigating changes of density and internal pressure, the distributions of atomic and sound velocities, and the temperature profiles in electronic and ionic subsystems of materials near the front of shock wave. These results are very relevant for the understanding the behavior of collimator materials used in LHC under 7 TeV proton beam.
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[1] A. Fasso et al. The physics models of FLUKA: status and recent development, CHEP 2003, LA Jolla, California, 2003 |
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| WEBX02 | Observation of Emittance Growth at the injection in the KEK PS Main Ring | injection, emittance, simulation, space-charge | 250 | ||
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We have been studying the emittance growth and beam loss mechanism during the injection period of the 12 GeV main ring of the KEK proton synchrotron to achieve higher intensity. The typical beam loss is about 30 % during the injection period of 500 milliseconds for the high intensity operation. Measurement of the transverse beam profiles using flying wires has revealed a characteristic temporal change of the beam profile within a few milliseconds after the injection. Horizontal emittance growth was observed when the horizontal tune was close to the integer. The effect was more enhanced for higher beam intensity and could not be explained with the injection mismatch. A resonance created by the space charge field was the cause of the emittance growth. A multiparticle tracking simulation program, ACCSIM, taking account of space charge effects has successfully reproduced the beam profiles.
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| WEBY01 | Commisioning of Electron Beam Cooling at S-LSR | electron, ion, beam-losses, feedback | 247 | ||
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S-LSR is a new compact ion cooler ring at Kyoto University. The circumference is 22.557 m. The commissioning of the electron cooling was started using the 7 MeV proton beam from November, 2005. The total length of the electron cooler is 1.63 m. In order to maximize the effective cooling length in the limited space, the magnetic field of the solenoid and the troid coils was calculated precisely by the 3D code. The electrostatic deflector for the electron and the steering magnet for the ion are placed in the troid. The performances of these devices are evaluated by the cooling measurements. Experiments using the electron cooling are also stared. One is an induction sweep cooling of the proton beam. It is an cooling with the assist of the induction acceleration and possible to reduce the cooling time of the hot ion beams like secondary particles. We also observe the behavior of the cooled ion beam in the small ion number case and the large ion number case. We discuss about the possibility of the phase transition of the proton in the former case and discuss about the coherent instability conditions in the latter case.
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| WEBY04 | Refined Models of Intrabeam Scattering | scattering, emittance, damping, coupling | 265 | ||
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We discuss two extensions of intrabeam-scattering theory. First, starting from the Bjorken-Mtingwa recipe, general formulae are derived for the three electro-magnetic intrabeam scattering growth rates, including non-ultrarelativistic terms and vertical dispersion, but maintaining a Gaussian beam approximation. A few applications demonstrate the importance of the vertical dispersion. Second, aside from electromagnetic interactions, hadrons may also undergo nuclear scattering off each other. We estimate the magnitude of this process, and argue that the loss rate due to “nuclear intrabeam scattering” could become significant in high-energy proton or ion storage rings, such as the LHC.
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| WEBZ01 | Correction of unevenness in Recycler beam profile | feedback, beam-loading, synchrotron, impedance | 244 | ||
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When a beam is confined between two rf barriers in the Fermilab Recycler Ring, it is observed that the longitudinal beam profile between the barriers is in general very uneven (typically about 20% for a beam of intensity 5E11). This leads to the consequence that the momentum-mined antiproton bunches may have an intolerable variation in bunch intensity. It is shown that the observed unevenness in beam profile is the result of a tiny amount (around 2%) of rf potential imperfection and a tiny amount (around 0.5%) of rf beam loading. The beam profile can be made even by feeding back the unevenness of the effective rf potential to the low-level rf.
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| WEBZ03 | A New High Rate Charged Particles Detector | hadron, controls, kaon, scattering | 256 | ||
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Sextant is a new Beam Spectrometer. This detector is based on a Time Projection Chamber(TPC)principle, using a gaseous detector called Micromegas. Thus, we have a better efficiency, with the minimum amount of material in the way of the beam. Moreover, using the TPC technique, the Mesh of the detector is positioned outside the high intensity region covered by the beam. Peformances of this detecor are very good in a high intensity hadron beams (spatial resolution : 70μm and time resolution 600ps). The integration of the front end on the PCB led to a very low noise for the entire detector. Main characteristics of the preamplifier are 1ns of rise time and a very low noise, lower than 600 μV rms. Sextant is an evolution of KABES, a beam spectrometer on NA 48II at CERN. This concept have shown very good performances and robustness.
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| THAW03 | RF Barrier Cavity Option for the SNS Ring Beam Power Upgrade | electron, space-charge, injection, target | 298 | ||
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RF barrier cavities present an attractive option for facilitating the path to higher beam intensity in the SNS power upgrade. Barrier cavities lead to flat longitudinal current densities, thus minimizing bunch factor effects. In addition to allowing more beam to be injected in this fashion, flat current profiles may lead to increased e-p instability thresholds due to reduced multipacting during the trailing stage of the bunch. Finally, it is possible to inject self-consistent beam distributions into barrier buckets, thus providing the additional advantages of uniform transverse beam density (good for meeting target constraints) and little or no halo (good for low losses). Simulations addressing all these issues will be presented and discussed.
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| THAY03 | Challenges for hadron (and leptons) nonscaling FFAGs | acceleration, lattice, betatron, resonance | 303 | ||
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The concept of Fixed-Field Alternating-Gradient (FFAG) accelerators was introduced about a half century ago. Few prototypes were built soon after and successfully placed in operation. Nevertheless, because of the perceived complexity of the early model magnets and design, the concept was soon abandoned in favor of cyclotrons, synchrotrons and linacs. It was subsequently occasionally revived for possible application as spallation neutron sources; but it was only recently that, because of the need of fast acceleration of muons, that FFAGs were re-considered and studied with more attention. Two prototypes were eventually built and operated at KEK for the acceleration of Protons. The interest indeed soon switched more steadily toward acceleration of protons (and electrons) as application for high-power proton drivers and medical accelerators. The paper describes the design procedure of a proton FFAG accelerator that employs a Non-Scaling lattice and exposes the main inherent issues, namely: the crossing of multiple resonances, space-charge at injection, and the fast acceleration rate that may impose limitations on the RF cavity hardware.
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| THAY04 | Review of high-brightness proton and ion acceleration using pulsed lasers | laser, target, ion, electron | 319 | ||
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In the last few years, intense research has been conducted on laser-accelerated ion sources and their applications. These sources have exceptional properties, i.e. high brightness and high spectral cut-off, high directionality and laminarity, short burst duration. We have shown that for proton energies >10 MeV, the transverse and longitudinal emittance are respectively <0.004 mm-mrad and <10-4 eV-s, i.e. at least 100-fold and may be as much as 104-fold better than conventional accelerators beams. Thanks to these properties, these sources allow for example point-projection radiography with unprecedented resolution. They also open new opportunities for ion beam generation and control, and could stimulate development of compact ion accelerators for many applications. We have shown [*] that there is an optimum in the laser pulse duration of ~200 fs-1 ps, with a needed laser energy level of 30 to 100 J, in order to achieve e.g. 200 MeV energy protons. Also, as, for such applications beam control is an essential requirement, we have developed [**] an ultra-fast laser-triggered micro-lens that allows tuneable control of the beam divergence as well as energy selection.
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[*] J. Fuchs et al., Nature Physics 2, 48 (2006). |
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| THAY07 | SC Spoke Cavity | linac, ion, hadron, beam-loading | 337 | ||
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Superconducting (SC) TEM-class spoke cavities have been an area of active research during the past decade with application to cw and pulsed ion linacs required for proposed facilities world-wide. Single- and multi-spoke geometries have been developed for use with ions over the full mass range and with velocities 0.2 < v/c < 0.8. Spoke cavities for this range, generally designed for 4 K operation, have several advantages over 2 K elliptical-cell cavities stemming mostly from the lower operating frequency. However, recent spoke-cavity results in 2 K operation, based on new and evolving cavity processing techniques such as clean assembly and hydrogen degassing, show very low rf losses even for high surface fields (EPEAK ~30 MV/m) required in operations. 2K results indicate even higher voltage gains per cavity with reduced heat loads are possible. Other implications of 2 Kelvin spoke cavity operation for ion linacs are discussed.
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| THAZ01 | Experience with high-power operation of the PSI proton accelerator facility | target, radiation, cyclotron, diagnostics | 274 | ||
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The PSI proton accelerator delivers a maximun current of 2 mA (routinely 1.9 mA) at 590 MeV. Ongoing developments aim at an upgrade of the beam current to 3 mA. This will result in an increase of the beam power from 1.2 to 1.8 MW on the pion/muon production targets and from 0.8 to 1.2 MW on the neutron spallation source SINQ. Our approach to the safe operation of a facility a these power levels will be presented. This includes considerations on the design of the cyclotrons, the beam lines and the tools to handle highly radioactive components. The protection of the facility via device controls, beam diagnostics and loss monitoring will be discussed. The specific requirements for operation with a sensitive liquid metal target like MEGAPIE will also be addressed.
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| FRAP07 | Summary of Working Group F | ion, laser, acceleration, synchrotron | 375 | ||
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